From Humors to Heavy Metals: The Hidden Dangers of Siddha and Unani Treatments
- Ganadhish Kamat
India’s medical landscape is uniquely pluralistic. Alongside modern evidence-based medicine, systems like Siddha and Unani continue to enjoy state patronage, institutional backing, and widespread public trust. Their cultural and historical significance is undeniable. But when evaluated through the lens of modern science, both Siddha and Unani reveal a fundamental problem: they are built on frameworks that fail basic standards of scientific validity, reproducibility, and safety.
Siddha System of Medicine
Siddha is one of the oldest traditional medical systems, believed to have originated in South India, especially Tamil culture. It is attributed to ancient sages called Siddhars. This system is prevelant in Tamilnadu, parts of Keralam and Srilanka.
Like Ayurveda, Siddha is also Based on three humors (Mukkuttram): Vatham (air + movement), Pitham (fire + metabolism) and Kapham (water + structure). The health is believed to be depending on the balance among these three and all the diseases are believed to be due to imbalance. There is also strong emphasis on Diet (Pathiyam), Lifestyle and Spiritual factors. It also includes concepts like: 96 tattvas (elements governing body and mind) and that the idea that body, mind, and soul are interconnected
Diagnosis is holistic and often subjective, involving:
- Naadi (pulse diagnosis) – practitioner interprets pulse patterns
- Naa (tongue examination)
- Vizhi (eye examination)
- Sparisam (touch/temperature)
- Malam & Moothiram (stool and urine analysis) - Includes a traditional test where oil is dropped into urine to observe patterns
There is no standardized or reproducible diagnostic framework comparable to modern pathology.
The treatment is personalized and may include:
- Internal medicines
-
External therapies:
- Oil application
- Massage
- Fumigation
- Dietary restrictions (Pathiyam) – strict food rules based on condition
- Yoga and spiritual practices
Types of Siddha Medicines
Siddha is notable for extensive use of minerals and metals:
- Parpam – calcined powders (often contain metals like calcium, mercury)
- Chendooram – red oxide-type preparations (may contain mercury, arsenic)
- Chunnam – alkaline preparations
- Kudineer – herbal decoctions
- Calcination
- Grinding with herbal juices
- Repeated heating cycles
Unani System of Medicine
Unani medicine originates from ancient Greek medicine, especially teachings of Hippocrates and Galen, later developed by Arab and Persian scholars. It was introduced to India during medieval Islamic rule. Unani is particularly prevelant among Muslim communities and practiced in North India, Hyderabad, Karnataka and Maharastra. Unani is based on four humors: Blood (Dam), Phlegm (Balgham), Yellow bile (Safra), Black bile (Sauda). Each person is believed to have a unique temperament (Mizaj): Hot, cold, moist, or dry. The health is believed to depend on the balance of humors and temperament and diseases are believed to be caused by imbalance or disturbance.
Diagnosis involves:
- Pulse examination (Nabz)
- Urine and stool examination
- Observation of: Skin color, Body build, Sleep patterns and Appetite
Diagnosis is largely qualitative and depends heavily on practitioner interpretation.
Unani uses four main modes of treatment:
1. Ilaj-bit-Tadbeer (Regimental therapy)
- Cupping (Hijama)
- Leeching
- Bloodletting
- Sweating, massage
2. Ilaj-bit-Ghiza (Diet therapy)
- Specific dietary regimens to restore humor balance
3. Ilaj-bit-Dawa (Drug therapy)
- Herbal, mineral, and animal-based medicines
4. Ilaj-bit-Yad (Surgery)
- Minor surgical procedures (limited scope today)
Types of Unani Medicines
Common formulations include:
- Kushta – calcined metal/mineral preparations
- Majoon – semi-solid herbal mixtures
- Sharbat – syrups
- Arq – distilled extracts
As with Siddha, the claim is that processing neutralizes toxicity—but modern toxicology often disputes this.
Foundations That Don’t Meet Scientific Standards
In the nutshell both systems rely on pre-scientific theories of the human body:
- Siddha medicine is rooted in the concept of three humors—Vatham, Pitham, and Kapham—and claims health is a balance among these forces.
- Unani medicine, derived from Greco-Arab traditions, is based on the theory of four humors—blood, phlegm, yellow bile, and black bile.
These frameworks resemble ancient European medical theories that were abandoned after the rise of modern physiology, microbiology, and biochemistry. There is no empirical evidence that these “humors” exist, can be measured, or correlate with disease processes as understood today.
Modern medicine, by contrast, relies on validated mechanisms such as infection by pathogens, genetic mutations, immune responses, and biochemical pathways—none of which align with Siddha or Unani principle
Lack of Controlled Evidence
A defining feature of science is testability. Treatments must demonstrate efficacy through controlled clinical trials, ideally randomized and blinded.
Most Siddha and Unani treatments fail this test:
- Evidence is often anecdotal or based on classical texts.
- Studies, where available, are frequently small, poorly designed, or lack proper controls.
- There is minimal reproducibility across independent research groups.
For example, many Unani formulations claim benefits in chronic diseases like diabetes or arthritis, but fail to show consistent results in rigorous trials when compared with placebo or standard therapies.
Dangerous Ingredients and Toxicity Risks
One of the most concerning aspects is the use of heavy metals and toxic substances, often justified under the claim that traditional purification methods make them safe.
Siddha Medicine Examples
-
“Parpam” and “Chendooram” preparations
These frequently contain mercury, lead, or arsenic in processed form.- Mercury exposure can lead to neurological damage, kidney failure, and cognitive impairment.
- Lead poisoning is linked to anemia, developmental delay, and organ damage.
-
Thamira Parpam (copper-based)
Chronic copper toxicity can cause liver cirrhosis and neurological symptoms.
Despite claims of detoxification through traditional processes, modern analytical studies repeatedly find toxic levels of heavy metals in such preparations.
Unani Medicine Examples
-
Kushta preparations (calcined metals and minerals)
These may include lead, mercury, silver, or gold compounds.- Lead-containing Kushtas have been linked to lead poisoning, particularly in long-term use.
-
Majoon-e-Dabeed-ul-Ward (used for liver conditions)
Some formulations have been found adulterated or contaminated, posing additional risks. - Herbal formulations containing aristolochic acid-like compounds (in some traditional systems globally) have been associated with kidney failure and cancer, raising concerns about insufficient toxicological evaluation.
Contamination and Quality Control Issues
Unlike modern pharmaceuticals, which are manufactured under strict Good Manufacturing Practices (GMP), many Siddha and Unani products suffer from:
- Batch-to-batch inconsistency
- Microbial contamination
- Adulteration with steroids or conventional drugs (to produce quick results)
Investigations in India and abroad have repeatedly detected undisclosed pharmaceuticals (like corticosteroids or NSAIDs) in traditional formulations marketed as “natural.”
The Illusion of “Natural = Safe”
A major driver of popularity is the perception that these systems are “natural” and therefore harmless. This is misleading.
- Arsenic, mercury, and lead are natural—but highly toxic.
- Herbal compounds can have potent pharmacological effects, including harmful interactions with modern drugs.
For example:
- A patient taking a Siddha preparation for arthritis may unknowingly consume steroids or heavy metals, masking symptoms while causing long-term harm.
- A Unani liver tonic may worsen underlying liver disease due to toxic constituents.
Regulatory and Ethical Concerns
India officially recognizes Siddha and Unani under the AYUSH framework, but regulatory rigor is often weaker compared to modern pharmaceuticals:
- Limited requirements for clinical efficacy data
- Inadequate post-marketing surveillance
- Weak enforcement against misleading claims
This creates a system where treatments can be widely marketed without meeting the same evidentiary standards expected of modern drugs.
Cultural Respect vs Scientific Accountability
It is important to distinguish between cultural heritage and medical validity.
Siddha and Unani systems represent historical attempts to understand disease in the absence of modern science. They may offer insights into diet, lifestyle, and holistic care. But when it comes to treating serious diseases—diabetes, cancer, infections—their frameworks are not just outdated; they can be dangerous.
Conclusion
Siddha and Unani medicine persist not because they are scientifically validated, but because of tradition, institutional support, and public perception. Their core theories are incompatible with modern biology, their treatments lack robust clinical evidence, and some of their formulations pose clear toxicological risks.
In a country striving for scientific progress and improved public health, the continued promotion of such systems without rigorous evidence raises serious questions. Tradition deserves respect—but not exemption from scrutiny.
Thanks for putting your thoughts together. As a champion for Ayurveda and Siddha medicine my views are opposite to yours.
ReplyDeleteYou mention that all ancient medical practices including Ayurveda and Siddha rely on pre-scientific theory of Human body. That is a soft way of condemning the underlying idea. Granted that efforts to apply scientific principles to holistic medicine are recent but that does not take away the effectiveness and time-tested efficacy of these modalities. Ayurveda and Siddha have a claim to thousands of years of continuous use which modern medicine lacks.
To address your second point about "controlled clinical trials", you suggest that to be the gold standard, but is it really a gold standard? How representative are these controlled trials, surely sampling plays a role and we are assuming unbiased measurement. The issue with using these methods for certifying the efficacy of Ayurveda is that these methods need a complete reimagining for the Ayurveda approach, which is individualized medicine with its own underlying fundamental basis.
Use of metals in medicines is very specific to Ayurveda and Siddha. There are very detailed methods to process these medicines, typically passed down through family legacy. These medicines are used for very specific situations, its ok to test for toxicity but why write-off an entire set of remedies that have worked for several thousand years.
First, longevity of use is not the same as proof of effectiveness. Many practices persisted for centuries before being abandoned once properly tested—bloodletting is a classic example. The fact that Ayurveda and Siddha medicine have been used for thousands of years tells us they are culturally resilient, not that they are clinically effective or safe by modern standards. History is a record of belief and tradition—not a substitute for evidence.
ReplyDeleteOn clinical trials: I haven't mentioned that clinical trials are gold standard. But controlled trials remain the most reliable tool we have to separate actual therapeutic effect from placebo, natural recovery, and subjective interpretation. If a system claims efficacy, it must withstand objective scrutiny. The idea that Ayurveda requires a “different” standard of evidence is precisely the problem—science progresses by applying consistent, testable, and reproducible methods. If a treatment works, it should work regardless of the philosophical framework used to describe it.
The argument of “individualized treatment” is also not unique. Modern medicine already incorporates personalization—through precision medicine, pharmacogenomics, and adaptive trial designs—while still maintaining rigorous evaluation standards. Individualization cannot be a shield against testing; if anything, it makes careful evaluation even more necessary.
Regarding metals: the concern is not theoretical but empirical. Multiple studies have documented unsafe levels of heavy metals like lead, mercury, and arsenic in some Ayurvedic and Siddha formulations. Traditional processing methods, however elaborate, do not automatically guarantee safety—especially when variability, lack of standardization, and commercial scaling come into play. Testing for toxicity is not a dismissal; it is a basic requirement for any medicine intended for human use.
Ultimately, this is not about dismissing tradition—it is about protecting patients. Any system of medicine, ancient or modern, earns legitimacy not through age or philosophy, but through consistent, reproducible evidence of safety and efficacy. If certain Ayurvedic or Siddha treatments truly work, rigorous testing will validate them—and that should strengthen, not threaten, their place in healthcare.
In my blog on Ayurveda, I did mention that some Ayurvedic treatment may work as they have been arrived at by trial and errors over centuries. However there is lack of scientific understanding about the composition of these drugs such as, their mechanism of action, impurity profiles, degradation products, metabolism etc. These can lead to inconsistencies between batches which can not be controlled in absence of scientifically sound testing methods.
Anyway there are believers of other ancient unscientific practices like astrology and spiritual healing. I can't convince everyone.
Mr. Kamat’s comments are based on scientific logic . Hence dependable.
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